As a technique for improving braking performance and steering stability when a vehicle runs on a wet road surface (hereafter referred to as wet performance), the following method has been conventionally known: A plurality of main grooves extending in the tire circumferential direction are formed in the tread surface of the tire, and a plurality of width direction grooves, sipes, or the like extending in the tire width direction are formed in the land portions defined by these main grooves, thus enhancing the drainage performance of the tire on the wet road surface (for example, see Patent Literature (PTL) 1).